Reversible ratchet wrench



APM 19, i932. 1 A. HUMMEL 4 n REVERSIBLE RA'.I'C'HF'I'` WRENCH FiledMarch 29, 1950 l INVENToR.

sil- LuzsAJY u me! 7 ATTORNK Patented Apr. 19, 1932 UNITED sTATEs-PATENT OFFICEI LOUIS A. HUMMEL, F MILWAUKEE, WISCONSIN, ASSIGNOR, BYMESNE ASSIGNMENTS, TO SNAP-ON TOOLS, INC., 0F KENOSHA, WISCONSIN, ACORPORATION 0F DELAWARE REVERSIBLE RATCHET WRENCH Application led March29, 1930. Serial N0. 439,873.

This invention relates to ratchet devices and more particularly toreversible ratchets for wrenches, although certain features thereof maybe employed with equal advan tige for other purposes.

It contemplates more especially the provision of an improved ratchetdevice capable of instantaneous adjustment to enable reversal withoutwithdrawal or change in position of its application for nut turning orother purposes.

With known ratcheting devices, it is necessary to withdraw the wrench orlever from registry with the nut to permit the reversed applicationthereof so that turning in an opposite direction may be effected. Thentoo, several sets of pawls have been resorted to in effecting reversalby independent adjusted engagement; however, such expedients in theirknown form have not proven entirely satisfactory owing to the intricateconstruction thereof which is not conducive vto dependable and rapidoperation.

This invention contemplates a` function substantially similarto that;performed by the invention described in the assignees copendingapplication serially numbered 423,- 7 96 and filed January 27, 1930;however, the structure is greatly simplified and the oper- A ationrendered more dependable for 'conven-.

ient manipulation. This is an important factor in ratchet wrenches owingto the fact i that they are employed in restricted locations where theirmanipulation is diicult and v adjustments found inconvenient. Theprimary variants from the copending structure` consist in a farlessexpensive device which is an important commercial consideration vfrom the standpoint of production costs, although the-operation isimproved to the eX- tent of imparting greater dependability over a longperiod of time without necessary replacements.

One object f the present invention is to simplify the construction andimprove the operation of devices of the character mentioned.

Another object is to provide an inexpensive ratchet which is readilyreversible and 5 dependable in operation.

. trative embodiment of the present invention.

Still another object is to provide a ratchet having a unitary adjustmentfor effecting reversal without withdrawing the device from turningregistry.

A further object is the provision of a ratchet having a unitaryexteriorly accessible adjustment to control the ratcheting direct1on.

A still further object is the provision of a rotary pawl capable ofengagement with a ratchet in different positions to effect ratchetingreversal.

Still a further object is to provide novel spring means of inexpensiveconstruction for maintaining the ratchet device in predeterminedadjustment for selective directional operation.

Other objects and advantages will appear from the following descriptionof an illus- In the drawings:

Figure 1 is a view in lelevation of a device embodying features of thepresent invention, parts thereof being broken away to clarify .theshowing.

Figure 2 is a fragmentary side'view'in elevation of the device shown inFigure 1, it being shown in partial section taken substan- Ytially alongline II--II of Figure 1.

Y Figure 3 is a fragmentary view of the 8'0 wrench head with the pawl ina position opposite to that shown in Figure 1 Figure 4 is a view similarto Figure 3 with the pawl shown in its neutral position.

Figure 5 is a side view in elevation of the spring employed as a meansof maintaining the pawl inl adjusted position. v Figure 6 vis a frontview in elevation of the spring shown in Figure-5.

Figure 7 is a perspectiveview of the pawl shown in Figures 1 to 4. 1

The structure selected for illustration comprises a body 10 which issuitably recessed to define a circular chamber 11A for the reception ofa revoluble member 12. The member 95 12 is retained within the recess 11of the body 10 by means of a face plate 13 which con'` forms in contourtherewith for attachment by j means of suitable fasteners 14, in thisinstance four. The confronting external 'surfaces of 100.

aligned bores 16 in communication with the -interior thereof, therebyrota-tively receiving the corresponding shaped hubs 17 of the revolublemember 12 journalled therein.

In order to impart rotation to the revoluble member 12 responsive tooscillatory movement of the body 10, the periphery thereof is providedwith radially extending ratchet teeth 18 cut or otherwise formed forextension therefrom. As shown, a circular recess 19 is provided in thebody 10 to communicate with the chamber 11, it being inlongitudinal'alignment therewith to receive a correspondingly shapedpawl- 20 journalled for rotation therein with the periphery thereofpartially disposed in the chamber-11. To this end, the pawl 20 hasintegral axial aligned hubs 21 received in correspondingly shaped bores22 provided in the body 10 and closure j plate 13. A knob 22 having thestem 23 thereof pressed in a somewhat smaller aperture 24 providedaxially within a pawl hub 21 to establish fixed connection therewith,constitutes a manual rotary adjustment for the pawl 20. To enableratcheting of the revoluble member 12 in opposed directions by rotaryadjustment of the knob 22,', the pawl 20 has the periphery thereof.interrupted to define oo nfronting pawl/ teeth 25 and 26. The pawl teeth25 and 26 are complemental to the ratchet teeth 18 for independentmeshing engagement therewith depending upon the rotary position of thepawl 20 which is adjusted by the knob 22 to control the directionalrotation of the revoluble member or ratchet wheel 12. The pawl teeth 25and 26 are suiiiciently spaced to enable the desired rotary throw of thehead 10 for ratcheting purposes without interference withl the inactivepawl tooth, thereby partially rotating the pawl 20 about its axisresponsive thereto -until the next successive ratchet tooth 18 isengaged.

To maintain the awl 20stationary and in adjusted positions or thedesired directional ratcheting, a wire 27 o f spring steel or othersuitably tempered material possessing an inherent spring is, in thisinstance, shaped to define orA simulate a question mark comprising ashank 28 with its circularly curved body 29 in continuity therewith.vAlthough the spring 27 may take anothei form, this partlcular shapeserves very effectively lin that a transversely disposed extension 30bent from the shank 28 may be pivotally anchored in an aperture 31provided in the wrench body 10. In consequence thereof, the-spring 27 ispivotally confined betweenthe surface of the wrench head 10 and thecover plate 13 for oscillatory movement in a plane adjacent to the faceof the pawl 20. As shown, the

circularly curved body 29 of the spring 27 terminates ina transverselydisposed extension 32 in parallelism with the extension 30 and offsetfrom the longitudinal median line thereof for resilient engagement withthe cutout portion 33 defined by the interrupted periphery of the pawl20 occasioned by the formation of the pawl teeth 25 and 26 thereon. f 1

With the -arrangement of parts above described, any suitable device forturning may be detachably or otherwise associated with therevolublemember 12. In the present embodiment a polygonal spindle 34 extendsaxially through and/or from the` revoluble member 12, it beingpreferably though not essentially provided with a spring impelled detent35 of standard construction so that wrench sockets or other appliancesmay be detachably associated therewith. lThe manual pawl ladjusting knob22 may be provided with suitable indicia 36, in this instancedirectional on7 and off indicators. Movement of the pawl 20 in aclockwise direction (viewed from Figure 1) will cause the pawl tooth 26to engage the ratchet teeth 18 for rotating the revoluble member 12 in acorrespending direction to tighten or turn on a right hand threadedmember. Opposite pawl adjustment indicated by directional indicator offplaces the pawl tooth 25 in engagement with the ratchet teeth 18 toremove a correspondingly threaded member -or fastener, thereby enablingthe ratchet to function in opposed directions with but a single anddupabl pawl easily adjusted for the purpose set ort This occurs in thatthe directional tooth for turning of the pawl 20, thereby requiring therotationin unison of the wrench head 10 with the revoluble member 12, toimpart a turning couple thereto for nut turning or vother purposesthrough the medium ofthe spindle 34 attached thereto for axialprojection therefrom. l

With the return of the handle 37l which preferably though notessentially constitutes an integral extension of the wrench body 10, aforced reaction normal to surface (b) of either tooth 25 or 26, tends toimpart rotary movement to the pawl 20 to the extent'that there is apartial rotary transfer thereof sufficient to remove the engaged tooth25 or .2G-with the ratchet teeth 18 of the revoluble member 12, therebymomentarily allowing the pawl 20 to ride over the' ratchet teeth 18until a successive engagement isfefl'ected responsive tothe associationof the'handle37. For this purpose, the spring 27 yields to an extentsuiiicient to permit the displacement of the pawl for temporary toothdisengagement until the succeeding ratchet tooth 18 `is engagedresponsive to a change in the direction movement of thehandle 37 Theparticular succeeding ratchet tooth 18 which is engaged by the tooth or26 of the pawl 20 varies with the extent to which the wrench handle 37isl swung, and any angle of ratcheting may be resorted to for nutturning or other purposes, this being limited by the pitch of theratchet teeth'18 which constitutes the smallest ratcheting angle.

It will thus be apparent that the spring 27 serves to impart an urge tothe pawl 20 in one direction or the othei` depending upon the positionof the latter. This is effected owing to the fact that the springextension 32 bears against the surface (b) of the tooth 25 or 26 tomaintainthe other tooth in engagement with the ratchet teeth 18. It willbe observed that this takes place in that the spring '27 is displaceablelaterally on` both sides of the longitudinal medianline along its pointof pivotal anchor to the wrench body 10 owing to the lodgement of theeX- `tension 30 thereof in the aperture 31. In

short, the adjustment of the pawl 20 to transfer the ratchet engagementof the tooth 25 to the tooth 26 or v1ce versa shifts the point ofcontact between the spring extension 32 of the pawl 2O from one tooth tothe other said ratchet-wheel, thereby transmitting the toothed reactionin diametral line with the curved body portions of said pawl, and apermanently curved wire spring pivotally anchored in said head portionfor lodgement of the free end thereof between said teeth to maintain theadjusted position of said pawl.

2.v In a ratchet wrench, the combination with a wrench body havinga headportion,

a ratchet wheel journalled for rotary movement in said wrench head,there being a substantiallv circular recess in said wrench body forcommunication with said ratchet wheel, a pawl having diametral curvedbearing outlines in a circumference conforming to said circular recessfor conning rotation therein, an interrupted periphery on said pawl todefine opposed teeth movable with -said pawl into and out of engagementwith so that the disengaged pawl tooth serves as .i

a stop for the free extremity 27 which imparts an urge to the pawl 20 inthe direction of the tooth engagement thereof. The spring 27 is,therefore, effective to maintain the pawl 20- in its adjustedlpositions, it being fer of the pawl 2() to its neutral position (Figure4) coincident with the disengagement of both ratchet teeth 25 and 26with the ratchet teeth 18 is thus held by the spring 27 in that the freeextremity 32 thereof is disposed centrally within the cutout portion 33to maintain this position.

Various changes may bevmade in the embodiment of the invention hereinspecifically described without departing from or sacriiicing any of theadvantages of the invention as defined in the appended claims.

I claim:

1. In a ratchet wrench, the combination with a wrench body having a headportion provided with communicating circular recesses, a toothedratchet-wheel journalled in' one of said recesses, a pawl havingdiametrically disposed cylindrically curved body journalled for circularmovement in the other recess, said pawl to form oppositely directedteeth engageable with said ratchet-wheel, means for circularly swingingsaid pawl about the curved portions thereof with oneor the other of saidteeth into operative engagement with 32 of the spring worthy of notethat the transan interrupted periphery on

